A High Speed Downlink Packet Access (HSDPA) technology is a high speed downlink packet access technology for Wideband Code Division Multiple Access (WCDMA) and the Time Division-Synchronization Code Division Multiple Access (TD-SCDMA); in order to improve the utilization rate of resources, the main physical resource of the HSDPA is the shared channel shared by different users; the downlink includes the High Speed-Downlink Shared Channel (HS-DSCH) and the High Speed-Downlink Shared Control Channel (HS-SCCH) which are used for providing a support for the high speed downlink data service of different users; HS-SCCH is the shared control channel of the HS-DSCH and is used for scheduling the usage of the HS-DSCH among different users. The WCDMA base station sends corresponding control information on a certain code channel of the HS-SCCH code channel set monitored by a user based on whether each user has a data to send during the next HS-DSCH Transmission Time Interval (TTI), and applies the mask modulo-2 and scrambling on control information by using a specific User Equipment Identifier (UEID); wherein the corresponding control information is divided into a first part control information (part1) and a second part control information (part2) which are transmitted sequentially; the access user of each HSDPA at the receiving end detects all the code channels of the corresponding HS-SCCH code channel set in each HS-SCCH TTI and determines whether its own HS-SCCH part1 information appears according to the UEID of this user; if the part1 information of this user is detected, the corresponding decoding information is applied to starting the descrambling and despreading of the corresponding HS-DSCH channel immediately and simultaneously starting the decoding process of the corresponding HS-SCCH part2 to obtain the decoding information related to the corresponding HS-DSCH channel; then, after finishing collecting the HS-DSCH channel, the decoding process of the HS-DSCH channel is started according to the HS-SCCH decoding information; therefore, the accurate reception of the HS-SCCH is the precondition for receiving the HS-DSCH channel data information; the error reception or the loss of HS-SCCH information will seriously influence the reception of HS-DSCH channel. However, whether the reception of HS-SCCH is accurate or not depends on the detection of the part1 information thereof; the high false dismissal probability of HS-SCCH part1 detection will cause a great loss of HS-DSCH information; the high false alarm probability will cause a frequent start of HS-DSCH, thereby increasing power consumption; in addition, the high false alarm probability will cause a frequent false detection of the HS-SCCH code channel of other users and then causes a loss of the HS-SCCH information of this user, which also causes a great loss of HS-DSCH information.
The detection algorithm of HS-SCCH part1 is mainly performed by using the accumulated state metric information at the end of the part1 Viterbi decoding; for example, the detection is performed by using the ratio of the difference between the maximum accumulated state metric “max_metric” and the minimum accumulated state metric “min_metric” to the minimum accumulated state metric, that is:(max_metric−min_metric)/min_metric>threshold1.
However, with respective to this method, the false alarm probability is high and the false dismissal probability is unsatisfactory; the blind detection in standard applies the following algorithm:(max_metric−min_metric)/(zero_metric−min_metric)>threshold2, that is:
the ratio of the difference between the maximum accumulated state metric “max_metric” and the minimum accumulated state metric “min_metric” to the difference between the zero state accumulated metric “zero_metric” and the minimum accumulated state metric is compared with the threshold to determine whether there is the HS-SCCH information of this user. This detection algorithm is on the basis that the maximum metric of the mask scrambled code word is approximately equiprobably distributed in any Viterbi state at the end of the Viterbi decoding; the maximum metric is approximately equiprobably distributed in 256 states in the WCDMA convolution encoding; therefore, the probability that the maximum metric converges to 0 state is 1/256 on the HS-SCCH of other users; then the false alarm probability approximately approaches 1/256, wherein the threshold2 extremely approaches 1. This method has a better false alarm probability and a better average false alarm probability. However, when the sent user UEID and the UEID of this user satisfy a specific relationship, the false alarm probability is high; therefore, the detection solution of HS-SCCH part 1 need be further improved and enhanced.